Texture: look and feel of rock's surface Grain:particles of minerals or other rocks Igneous Rock:forms from cooling of molten rock Sedimentary Rock: forms when particles of other rocks or the remains of plants and animals are pressed and cemented together Metamorphic Rock:forms when existing rock is changed by heat, pressure, or chemical reactions
Outline
How geologists classify rocks
when studying rock, geologists observe rocks'
color
texture
mineral composition
Texture
useful when identifying rocks
some rocks are
smooth and glassy
rough and chalky
to describe rock's texture
use size, shape, and pattern
grain size
grain shape
grain pattern
no visible grain
Mineral composition
test rock with acid to determine if rock contains carbonates
Origin
3 major group of rocks
igneous rocks
forms when molten rock cools
sedimentary rocks
forms when particles of rock, plants, and animals are pressed and cemented together
metamorphic rocks
forms when existing rock is changed by heat, pressure, or chemical reactions
Table of Contents
5.1 Classifying Rocks
Vocabulary
Texture: look and feel of rock's surface
Grain:particles of minerals or other rocks
Igneous Rock:forms from cooling of molten rock
Sedimentary Rock: forms when particles of other rocks or the remains of plants and animals are pressed and cemented together
Metamorphic Rock:forms when existing rock is changed by heat, pressure, or chemical reactions
Outline
Diagram